How the hell do you know that? You can't know which IP address kamrul50 uses if you don't have anything to do with that account.
The air of authority is how most bluffs and scams are passed off and users suckered.
"I say this is true, so you will believe it is true and when I say hand over what I want, you will" is how the voice of authority scams work.
Hello,sir. Abdullah500 is my account but isn't kamrul50 my account and I want to proof any you. Please tell me, Want you any proof from me.